Octyl Salicylate

So, why isn’t anyone discussing using Octyl Salicylate in their transdermal homebrews? Octyl Salicylate has been proven to be an effective penetration enhancer when used with Testosterone. In the attached study, OS was shown to increase the penetration of testosterone by a factor of six. That is a huge number. In addition, it is the first ingredient that Par discusses in his transdermal article. Granted, its not cheap. I paid $30 for 500 ml’s. Its not often that we have solid evidence (or studies) relating to the transdermal absorption of hormones with various penetration enhancers. We do have it with OS. The attached article from Science Magazine is very interesting.

I have had this discussion with a few people before. I don' tlike OS. The reason is that there is only one article that says it penetrates well(This one you show is the same one and only one that Par uses for his backup of OS).. There is way to many articles like this one I have posted that say it does nothing. OS is a UV ray blocker and thats all I have found. But lets definately keep looking. The homebrew will never be "perfect" and can always be improved. Talk to ya.

Walters, K.A., K.R. Brain, D. Howes, V.J. James, A.L. Kraus, N.M. Teetsel, M. Toulon, A.C. Watkinson and S.D. Gettings. Percutaneous Penetration of Octyl Salicylate from Representative Sunscreen Formulations through Human Skin In Vitro. Fd. Chem. Toxic. 1997. 35: 1219-1225. [Reprinted with permission from Elsevier Science]
octyl salicylate - 06969-49-9
The human skin penetration of [14C]octyl salicylate from two representative sunscreen vehicles was determined in vitro. 3H-sucrose was incorporated into all formulations and provided a marker for membrane integrity. When applied as a finite dose in an oil-in-water emulsion vehicle containing 5% (w/w) octyl salicylate, the average total absorption of 14C over 48 hr was 0.65 ± 0.16% of the applied dose (representing a total amount permeated of 1.58 ± 0.36 ug/cm2). When applied as an infinite dose in the oil-in-water emulsion vehicle the average total absorption of 14C over 48 hr was 0.47 ± 0.22% of the applied dose (representing a total amount permeated of 27.54 ± 13.91 ug/cm2). When applied as a finite dose in a representative hydroalcoholic formulation containing 5% (w/w) octyl salicylate, the average total absorption of 14C over 48 hr was 0.23 ± 0.05% of the applied dose (representing a total amount permeated of 11.28 ± 2.55 ug/cm2). The penetration of [14C]salicylic acid [applied at a concentration of 2.7% (w/w), in the oil-in-water emulsion] was also determined. When applied as a finite dose the average total absorption of 14C over 48 hr was 1.14 ± 0.23% of the applied dose (representing a total amount permeated of 1.65 ± 0.39 ug/cm2). These results suggest that the in vitro human skin permeation of octyl salicylate is relatively low. The amounts of octyl salicylate and salicylic acid permeated when applied in similar vehicles were remarkably similar over 48 hr (1.58 ug/cm2 and 1.65 ug/cm2, respectively). This suggests the possibility that the 14C label appearing in the receptor fluid may, in both cases, represent salicylic acid. If this is the case, then it is possible that the amount of octyl salicylate permeating through the skin is much less than that suggested by the data obtained here. This supposition is, however, entirely speculative and has yet to be confirmed experimentally.

Curt, thanks for the quick response. Do you have any similar studies that use sex hormones or something similar to testosterone? The reason being is that 3H-Sucrose may not be very representative of testosterone in terms of molecular weight, solubility, polarity, etc. These are all factors that are very important to the absorption of a drug through the skin.

Science is a very respected pub and usually does not publish junk. In addition, 1 study in favor using test is more research than some of the other ingreditents that are being used. But I agree, it is still not a lot to go on.

Originally posted by bow Curt, thanks for the quick response. Do you have any similar studies that use sex hormones or something similar to testosterone? The reason being is that 3H-Sucrose may not be very representative of testosterone in terms of molecular weight, solubility, polarity, etc. These are all factors that are very important to the absorption of a drug through the skin.

If thats the case then this test was done with test. We do not use test in the solutions. 1-test and 4-ad . These different in molecular structure and weight from the study as well. Just food for thought. talk to ya

If thats the case then this test was done with test. We do not use test in the solutions. 1-test and 4-ad . These different in molecular structure and weight from the study as well. Just food for thought. talk to ya

but the weights are simililar enough, and the structures are based on the sterol structure.

Yes i realize they are close but not the same thats all. the test was based on test and its the only study out there.. If we can find that it works then cool. But one other thingwe don't want the brew to get too complicated and expensive. If we find it to be good and works diff from the other pe's then we can add it but if it works by the same action as one of the other pe's then there is no sence to add it. Talk to ya.

OS seems to be an effective PE for the reason that it can open up the layers on the SC. Not to mention we have definite proof that it works with hormonal compounds (study bow posted). Heres what Par had to say about it in his article:

The second mechanism is via disruption of the stratum corneum's highly ordered lipid bilayers. As we described earlier, it consists of lipophilic lipid regions, each separated by a thin layer of water. This aqueous layer is detrimental to the diffusion of lipophilic substances. Certain penetration enhancers such as unsaturated fatty acids, padimate O, and possibly isopropyl myristate and octyl salicylate, can disorder these bilayers, forming separate pools of oil within the stratum corneum's intracellular spaces, which lipophilic compounds can diffuse through much more freely (3,19,20). This would also be expected to help hydrophilic compounds, if aqueous pools were formed, and there is data suggesting both the capability of "straight through aqueous channels" (21), as well as enhancement with a combination of propylene glycol, which is hydrophilic, and unsaturated fatty acids

Originally posted by ndn diablo OS seems to be an effective PE for the reason that it can open up the layers on the SC. Not to mention we have definite proof that it works with hormonal compounds (study bow posted). Heres what Par had to say about it in his article:

The second mechanism is via disruption of the stratum corneum's highly ordered lipid bilayers. As we described earlier, it consists of lipophilic lipid regions, each separated by a thin layer of water. This aqueous layer is detrimental to the diffusion of lipophilic substances. Certain penetration enhancers such as unsaturated fatty acids, padimate O, and possibly isopropyl myristate and octyl salicylate, can disorder these bilayers, forming separate pools of oil within the stratum corneum's intracellular spaces, which lipophilic compounds can diffuse through much more freely (3,19,20). This would also be expected to help hydrophilic compounds, if aqueous pools were formed, and there is data suggesting both the capability of "straight through aqueous channels" (21), as well as enhancement with a combination of propylene glycol, which is hydrophilic, and unsaturated fatty acids

My main reason for not including the OS is the fact that there are high concentrations of other PE's that work by the same mechanism of action. Simply adding more of the already present PE's would have pretty much the same effect.

I'm not trying to dispute the fact that OS has been proven to be an effective PE but merely that there are diminished returns on the absorption.

For instance, some bros are under the impression that doubling the dose of an AAS will give double the gains. This is obviously not the case. There will be a certain amount of increased growth but it will not be double or even close. The same concept applies to PE's in general.

There will no doubt be an increase in absorption when adding OS to a brew but the gain in absorption does not offset or justify the cost of overhead, IMO. Especially when viewed in terms of a DMSO brew...

It is important to point out here that the decision to add OS to a brew is neither right or wrong. It is a personal choice and HAS been proven to increase absorption. However, the choice has to be made with the knowledge that there may only be a marginal increase in absorption since other PE's work by the same mechanism and the bulk of work will be done by DMSO.

Originally posted by SteveDFW I agree with BDC. I am presently using OS but when I run out I will no longer use it. It is the most costly ingredient in the homebrews (excluding PHs).

Yes, but it only makes up 5 to 9% of the formula. I am still trying to get Melissa at LemeLange to get it for me. BDC, isn't there a odorless DMSO product out there? I know it is mainly the metabolites of DMSO that stink, but the odorless stuff may be of value in a formula that only uses 5 to 10%. What do you think?

There is sno "odorless" stuff. the more pure it is the less it makes you stink. Like 99.99% is good.The USP stuff... The technical grade that melisa sells is not that pure and could lead to stick.Hope that helps. Talk to ya.

Originally posted by curt2go There is sno "odorless" stuff. the more pure it is the less it makes you stink. Like 99.99% is good.The USP stuff... The technical grade that melisa sells is not that pure and could lead to stick.Hope that helps. Talk to ya.

I used the 99.9% in in my brews at 10% and 15% as previous posted elsewhere.